German Patent Application No. 24 33 555 describes a conventional transformer arrangement.
An important criterion for the reliable operation of an air bag is that switching operations or short-circuits in a primary circuit of the transformer must not erroneously deploy the air bag. The transformer absorbs a relatively high magnetic energy in sudden startup and shutdown operations; this energy is discharged mainly in a load connected in a secondary circuit. With an air bag, this load is the firing pellet (squib) resistor. If the energy fed into the squib resistor exceeds a predetermined threshold, the air bag is deployed.
Therefore, the object of the present invention is to provide an arrangement of the type defined in the preamble that will avoid unintentional deployment of the air bag when sudden startup or shutdown operations occur in the primary circuit of the transformer or short-circuits occur between the squib and the power supply lines of the vehicle battery.